Pesticide Usage Report: Top fruit crops 2016

Summary

This report presents information from a survey of the pesticide usage practices of top fruit growers in Northern Ireland in 2016.  This is the ninth pesticide survey to be conducted on top fruit crops in the region since 1992. In contrast with previous surveys, top fruit holdings comprising less than 2 hectares were excluded as it was considered that they were not commercially viable and did not contribute to overall pesticide usage data. There were an estimated total of 215 top fruit holdings in Northern Ireland in 2016, but only 138 were above 2 hectares, providing the survey population. Since the previous survey, there was a marginal increase in the total area of top fruit crops grown to 1526 hectares, suggesting consolidation within the industry, although the area of Bramley apples grown decreased by 1%. A sample of 53 growers was selected to provide information on crop applications, storage treatments and orchard floor treatments.  An estimated 95% of all top fruit crops were grown in County Armagh, with Bramley apple orchards accounting for 97% of the total top fruit grown in Northern Ireland.  There were an estimated 44,824 tonnes of Bramley apples harvested in 2016, a 17% increase compared to 2014.

Overall, an estimated 35.5 tonnes of pesticide active ingredients were applied to 46,770 spray hectares.  The pesticide-treated area increased by 14% compared with 2014, and the weight of active ingredients applied decreased by 3%.

Fungicide application accounted for more than 65% of total pesticide use (including ‘other’ products) by area treated and weight applied. When compared with 2014, the area treated with fungicides increased by 10%, but the weight of fungicides applied decreased by 1%.    Mancozeb (21%), captan (15%), dithianon (11%), pyrimethanil (10%) fenbuconazole (9%) and dodine (8%) were the fungicide active ingredients most commonly used on top fruit crops, collectively accounting for 74% of fungicide-treated area. An estimated 80% of all fungicide applications were applied to control apple scab (Venturia inaequalis).

Insecticide and acaricide application represented 6% and <1% of total pesticide use by area treated and weight of active substance applied, respectively. The area treated with insecticides and acaricides increased by 52% when compared with 2014. There was a notable decline in the use of the organophosphate insecticide chlorpyrifos (-63%) and the carbamate, pirimicarb (-73%). It should be noted that, from 31st March 2016, all uses of chlorpyrifos were revoked except for treatment of brassica crops in peat blocks via gantry-mounted sprayers. The use of the pyrethroid insecticide cypermethrin increased almost 4-fold, representing 63% of total insecticide application. A two-fold increase in the use of the moulting accelerator, methoxyfenozide since 2014, was also recorded. Aphid control accounted for 34% of insecticide application and a further 51% was attributed to ‘general insect control’. No insecticides containing neonicotinoid active ingredients were recorded in use on top fruit orchards in 2016.

Herbicide application represented 4% of total pesticide use by area treated and weight applied. Overall, the area treated with herbicide decreased by 3%, and the weight of herbicides applied decreased by 19%, when compared with 2014.  Glyphosate and the formulation dicamba/MCPA/mecoprop-P were the herbicides most frequently used accounting for 77% of total herbicide application.  The most common weed management practice was to apply herbicides in strips under the tree canopy and mow the inter-row grass area between the rows of trees, with 96% of growers using this method.  The remaining 4% of growers either mowed or grazed the strips under the tree canopy in addition to the inter-row area.

Growth regulators accounted for 4% of the pesticide-treated area and less than 1% of the total weight of pesticide applied.  Paclobutrazol, prohexadione, prohexadione-calcium and gibberellins were the only growth regulator active ingredients applied.  Prohexadione and prohexadione-calcium accounted for 67% of the area treated with a growth regulator and 78% of the total weight of growth regulator applied. In 2016, orchard growth was advanced over typical spring seasons, by between seven and ten days, which initiated earlier flowering and fruit set occurred over a protracted period.  

An estimated 10 tonnes of ‘other products’, which included foliar feeds, trace elements and calcium-based products, were applied to the crops during this survey period, a similar figure compared to 2014.  The majority of applications were to treat potential nutritional disorders.

Data were also collected on post-harvest storage treatments applied to top fruit crops. An estimated 24,475 tonnes of apples were stored, of which only Bramley apples were treated accounting for 21,254 tonnes. A total of two pesticide active ingredients were recorded in use on stored top fruit crops in 2016, the fungicide cyprodnil/fludioxinil and 1-Methylcyclopropene being the most common accounting for 97% of apples treated. Bramley apples represented 99% of all stored apples.